共查询到20条相似文献,搜索用时 15 毫秒
1.
流体随机Petri网与混合Petri网的比较分析 总被引:2,自引:0,他引:2
流体随机Petri网和混合Petri网作为传统Petri网的拓展,可以建模离散成分和连续成分并存的混合系统,也可用于解决离散模型的状态空间爆炸问题.由于这两种建模机制远未发展成熟,分析比较它们的异同点有助于机制本身的进一步发展完善,有助于为特定的应用选择合适的建模方法.本文讨论了流体随机Petri网和混合Petri网的定义、连续标识、分析方法、以及相互转换的可能性.结论是这两种建模机制是互补的,各自适合于特定的应用场合. 相似文献
2.
Comparison of Hybrid Systems and Fluid Stochastic Petri Nets 总被引:1,自引:0,他引:1
Hybrid Systems are modelsof interacting digital and continuous devices with applicationsin the control of aircraft, computers, or modern cars for instance.Concurrently, Fluid Stochastic Petri Nets (FSPNs) have been introducedas an extension of stochastic Petri nets to model physical systemsthat contain continuous fluid quantities controlled by discretelogic, as well as a means to deal with the possible state explosionof discrete models. Of course, an FSPN is by definition a hybridsystem but in this paper, we compare a general hybrid systemsformalism with FSPN formalism. The conclusion of this paper,suplemented by some examples, is that fluid stochastic Petrinets and hybrid system formalism can be converted from one tothe other. Although there is a price to pay for such a conversion,the conversion can transfer the solution methods from one tothe other and thus help the development of both formalisms. 相似文献
3.
混合动态系统的混合Petri网(HSPN)模型 总被引:3,自引:0,他引:3
针对混合动态系统,提出一种混合Petri网(HSPN)模型,分析了该模型具有的特点及其运行规则。以冶金加热炉为例,给出了该系统的HSPN模型。 相似文献
4.
基于混合Petri网的一类混合系统的动态分析 总被引:2,自引:2,他引:2
利用混合Petri网对一类典型的混合系统--模式切换系统进行建模和分析;提出模式切换系统动态平稳性的概念;给出了二模式切换系统的平稳条件以及求解平稳点的算法,并用实例进行了说明。 相似文献
5.
6.
区间速率连续Petri网模型行为分析研究 总被引:1,自引:0,他引:1
讨论了区间速率连续Petri网模型的行为分析问题.通过划分标识等价类提出了任意标识下区间速率连续Petri网各个迁移瞬时引发速率的求解方法,并在此基础上给出了区间速率连续Petri网的行为演变算法.同时给出了区间速率连续Petri网行为演变的混杂自动机模型构造方法.应用例子表明了所提出行为分析方法的有效性. 相似文献
7.
基于Petri网的混合动态系统接口层设计方法及其在热连轧中的应用 总被引:1,自引:0,他引:1
接口的设计是整个混合动态系统实现的关键。模拟模块化的思想,提出了基于Petri网转换器的实现方法,并且设计了热连轧过程从数值到符号的转换接口,为下一步实现实时调度奠定了基础。 相似文献
8.
基于混合随机Petri网的一类混合系统的模型及稳定性 总被引:4,自引:0,他引:4
混合动态系统是包含离散事件系统(DES)和连续变量系统(CVS)的复杂系统。讨论了一类每个离散状态包含一个连续动态系统,且离散事件具有Markov链性质的随机混合系统,在提出利用混合随机Petri网的建模方法的基础上,给出混合均方稳定的概念、稳定性和可镇定条件,最后以一个简单的例子做子说明和仿真。 相似文献
9.
Xenofon D. Koutsoukos Kevin X. He Michael D. Lemmon Panos J. Antsaklis 《Discrete Event Dynamic Systems》1998,8(2):137-173
In this paper, timed Petri nets are used to model and control hybrid systems. Petri nets are used instead of finite automata primarily because of the advantages they offer in dealing with concurrency and complexity issues. A brief overview of existing results on hybrid systems that are based on Petri nets is first presented. A class of timed Petri nets named programmable timed Petri nets (PTPN) is then used to model hybrid systems. Using the PTPN, the stability and supervisory control of hybrid systems are addressed and efficient algorithms are introduced. In particular, we present sufficient conditions for the uniform ultimate boundness of hybrid systems composed of multiple linear time invariant plants which are switched between using a logical rule described by a Petri net. This paper also examines the supervisory control of a hybrid system in which the continuous state is transfered to a region of the state space in a way that respects safety specifications on the plant's discrete and continuous dynamics. 相似文献
10.
基于Petri网的离散系统仿真方法研究 总被引:3,自引:0,他引:3
将Petri网(P网)的概念和方法应用于离散系统仿真的方法论研究中。提出了基于P网的系统化的离散系统仿真建模方法,重点研究了基于P网的仿真策略,探讨了P网仿真策略的实现方式,并对其特点进行了分析和讨论。 相似文献
11.
在Petri网精化概念的基础上,给出一种解决Petri网结点爆炸问题的方法,该方法针对精化的定义,从库所和变迁的约束条件入手,分析结点精化的可行性和方法,并给出证明。该方法的建立为今后利用Petri网进行建模提供了必要帮助。 相似文献
12.
为了实现R.David和H.Alla所定义的混杂Petri网模型行为分析的正确性,提出了一个通用的模型动态演变方法.该方法给出了基于线性规划方法的混杂Petri网瞬时引发速率求解方法,解决了有效冲突情形下的瞬时引发速率求解问题.分析了改变不变行为(Invariant Behavior,简称IB)状态事件之间的相互作用及其对模型演变正确性的影响,同时提出了判定改变IB状态事件的方法.例子表明了所提出的理论与方法对混杂Petri网模型动态演变正确求解的重要性和有效性. 相似文献
13.
本文给出了时间Petri网对企业经营过程中的生产流水线进行建模,并将之与工作流管理系统相结合以进行仿真分析的一种方案;结合实例说明方案的实施过程,其中关键在于约束条件的充定;通过消除“瓶颈”优化生产流水线,实现企业经营过程的有效重组。 相似文献
14.
为了解决“顾客投诉”等这一类业务处理问题,提出了用Petri网精细化操作解决问题的方案。定义了一种子网,用这种子网分别对Petri网中的某些变迁进行细化,得到更细致、更精确的Petri网。研究了Petri网精细化操作的性质保持问题,给出了这种精细化操作保持结构有界性、守恒性、可重复性、相容性和活性的充分条件。本文的结果可为复杂大系统的分析提供重要手段,并特别适合于一类业务系统的描述和验证,具有一定的实用价值。 相似文献
15.
16.
有色Petri网的一种面向对象扩展形式 总被引:1,自引:0,他引:1
Petri网与面向对象的结合一直是一个令人感兴趣的研究课题。本文把有色Petri网引入到面向对象方法中,提出了一种面向对象的扩展有色Petri网,简称为OECPN, 相似文献
17.
18.
19.
Miryam Barad 《国际通用系统杂志》2013,42(6):565-582
This paper describes the fundamental concepts and characteristics of Petri nets (PNs) that make them a significant tool for modeling and analyzing asynchronous systems with concurrent and parallel activities and follows the extensions that improved the implementation capabilities of the original PNs. Their first and most relevant extension was time modeling, a vital aspect of system performances not considered in the original version. There are several possibilities for introducing time in PNs. Among them, a technique that associates time with places is presented in some detail. As PNs tend to become cumbersome and time consuming when large and complex systems are involved, a method for decomposing timed PNs of open queuing networks is reviewed here. Though initially developed as an information/computer-based technique, PNs were immediately adopted in a variety of application areas, such as manufacturing, design, planning and control. Viewed through a more recently developed programming perspective, the ordinary PNs became “high level” PNs suitable for defining different data types and for applying hierarchical approaches. It is expected that the robust theoretical basis of this tool coupled with its visual and flexibility features will continue to appeal to researchers and practitioners alike in a variety of domains and as a result will continue to evolve and expand. 相似文献